diff --git a/homeassistant/components/airnow/diagnostics.py b/homeassistant/components/airnow/diagnostics.py
new file mode 100644
index 00000000000..284fd65013b
--- /dev/null
+++ b/homeassistant/components/airnow/diagnostics.py
@@ -0,0 +1,53 @@
+"""Diagnostics support for AirNow."""
+from __future__ import annotations
+
+from typing import Any
+
+from homeassistant.components.diagnostics import async_redact_data
+from homeassistant.config_entries import ConfigEntry
+from homeassistant.const import (
+    CONF_API_KEY,
+    CONF_LATITUDE,
+    CONF_LONGITUDE,
+    CONF_UNIQUE_ID,
+)
+from homeassistant.core import HomeAssistant
+
+from . import AirNowDataUpdateCoordinator
+from .const import DOMAIN
+
+ATTR_LATITUDE_CAP = "Latitude"
+ATTR_LONGITUDE_CAP = "Longitude"
+ATTR_REPORTING_AREA = "ReportingArea"
+ATTR_STATE_CODE = "StateCode"
+
+CONF_TITLE = "title"
+
+TO_REDACT = {
+    ATTR_LATITUDE_CAP,
+    ATTR_LONGITUDE_CAP,
+    ATTR_REPORTING_AREA,
+    ATTR_STATE_CODE,
+    CONF_API_KEY,
+    CONF_LATITUDE,
+    CONF_LONGITUDE,
+    # The config entry title has latitude/longitude:
+    CONF_TITLE,
+    # The config entry unique ID has latitude/longitude:
+    CONF_UNIQUE_ID,
+}
+
+
+async def async_get_config_entry_diagnostics(
+    hass: HomeAssistant, entry: ConfigEntry
+) -> dict[str, Any]:
+    """Return diagnostics for a config entry."""
+    coordinator: AirNowDataUpdateCoordinator = hass.data[DOMAIN][entry.entry_id]
+
+    return async_redact_data(
+        {
+            "entry": entry.as_dict(),
+            "data": coordinator.data,
+        },
+        TO_REDACT,
+    )
diff --git a/tests/components/airnow/test_diagnostics.py b/tests/components/airnow/test_diagnostics.py
new file mode 100644
index 00000000000..76a8a1dc0b2
--- /dev/null
+++ b/tests/components/airnow/test_diagnostics.py
@@ -0,0 +1,43 @@
+"""Test AirNow diagnostics."""
+from homeassistant.components.diagnostics import REDACTED
+
+from tests.components.diagnostics import get_diagnostics_for_config_entry
+
+
+async def test_entry_diagnostics(hass, config_entry, hass_client, setup_airnow):
+    """Test config entry diagnostics."""
+    assert await get_diagnostics_for_config_entry(hass, hass_client, config_entry) == {
+        "entry": {
+            "entry_id": config_entry.entry_id,
+            "version": 1,
+            "domain": "airnow",
+            "title": REDACTED,
+            "data": {
+                "api_key": REDACTED,
+                "latitude": REDACTED,
+                "longitude": REDACTED,
+                "radius": 75,
+            },
+            "options": {},
+            "pref_disable_new_entities": False,
+            "pref_disable_polling": False,
+            "source": "user",
+            "unique_id": REDACTED,
+            "disabled_by": None,
+        },
+        "data": {
+            "O3": 0.048,
+            "PM2.5": 8.9,
+            "HourObserved": 15,
+            "DateObserved": "2020-12-20",
+            "StateCode": REDACTED,
+            "ReportingArea": REDACTED,
+            "Latitude": REDACTED,
+            "Longitude": REDACTED,
+            "PM10": 12,
+            "AQI": 44,
+            "Category.Number": 1,
+            "Category.Name": "Good",
+            "Pollutant": "O3",
+        },
+    }